Steven Porges’ Multiple Level Visceral Model
by Jerome Liss, M.D.
A New Understanding of “Visceral Experience”
Psychotherapy can profit from a new neurophysiological model. It will help both the psychotherapist and the patient understand the dynamics of emotions. Steven Porges, at the University of Illinois, has presented the functional structure of the visceral nuclei.(Porges, 1996,2001,2003) These nuclei are found at the bottom of the brain, specifically, in the brain stem. Therefore, they represent the final output of the brain. Their task is to regulate our visceral functions: heart, lungs and digestive system. Thus our “visceral experiences” – a knot in the stomach, pressure in the chest, the heart beating hard -- are determined by these visceral nuclei. These nuclei send impulses through the vagus nerve to the body’s internal organs.
The visceral nuclei are, in turn, regulated by higher brain levels. At the same time these nuclei receive feedback from the visceral organs themselves. Such feedback further reguazlates the visceral nuclei. And how does the “visceral experience” occur? The visceral organ feedback is then sent to higher brain levels. Nauta (1972) noted that the visceral feedback goes upwards in the brain, step by step, by means of “small climbing chains.” The visceral feedback finally reaches the highest level, the orbito-frontal cortex, which registers the conscious feeling of the visceral feedback. This gives us our “visceral experience.”
The Three Visceral Levels
Level I: The Dorsal Vagal Complex
Porges proposes three levels of visceral regulation: The lowest level is called the Dorsal Vagal Complex (DVC), and is composed of the input nucleus, called the Nucleus Solitarius, as well as the output nucleus, called the Dorsal Motor Nucleus of the Vagus. He shows that this system was already present in fish and amphibians. (The phylogenetic correlation between the each visceral level and the development of earlier species is a special contribution of Porges’ Multiple Level Visceral Model.) This first visceral level regulates normal visceral processes during rest and recuperation, organizing digestive processes (secretions, peristalsis), slowing the heart and slowing the breathing.
The same system, however, is used for the organism’s first major defense when there is a sudden danger. How does this happen? The sudden danger -- usually the presence of a larger predator – creates an “overflow” of the visceral nuclei and the creature “freezes” and “plays dead.” The organism becomes completely immobile (the behaviour), and the visceral processes become blocked. “Freeze” means that the immobilized state is hypertonic, that is, there is a high tone of the voluntary muscles. But the “Stop!” and “Play dead!” defensive strategy can also occur with a total loss of muscular tone. In that case the organism goes into “collapse.” In human beings, this takes place the moment that we receive “disastrous” news (failure, death, separation, violence, threat, robbery) and we feel, “the bottom drops out,” “all is lost,” “my belly becomes an empty hole.” This is what happens when we suffer from trauma. The experience is emotionally very painful.
Level II: The Aggression-Fear System
The second visceral level is the aggression-fear defense system. Here is the neuronal pattern: A higher sub-cortical center, called the amygdala, receives perceptual stimuli and mobilizes the “activating” defense system of fight or flight.(LeDoux,1996) The amygdala sends messages upwards to influence cortical thinking, and horizontally to influence basal ganglia action. At the same time the amygdala sends messages downwards to the paraventricular nucleus of the hypothalamus. The paraventricular nucleus sends sympathetic messages still further downwards, directly to the spinal cord, by-passing the brain stem visceral nuclei, and from there the messages are passed on to the various visceral organs. The creature is prepare for the active response of fight or flight: the heart rate is increased, breathing becomes rapid, digestion stops, blood is shunted from the digestive organs to the voluntary muscles, and the smooth muscles that surround the visceral organs become tense, connected to our feeling of visceral tension or a “knot” in the belly. Thus our amygdala-based “fight or flight” system creates a visceral response that helps us when we attack with rage an opponent or when we flee with fear an enemy who is stronger than ourselves.
Porges points out that this fight or flight system, which is “higher” than the “collapse” and “play dead” DVC, first developed with the reptiles.
Level III: The Ventral Vagal Complex
The third and highest visceral system, called the Ventral Vagal Complex (VVC), represents our positive “social interaction” system. This system allows subtle and very immediate changes in our visceral organs, especially of our heart rate and breath. Such immediate changes correlate with approach or distancing social behaviour. In addition, while the two lower “defense systems” mobilize hormones, neuromodulators and peptides (the chemical accompaniment that reinforces the neuronal defense systems), this higher VVC system, in contrast, permits visceral regulation with little impact upon the associated chemical system.
How can this affect our emotions? Mobilization of the chemical system to reinforce the neuronal system results in greater overall power. But it also means that there is less capacity for precise calibration, especially for decreasing the defensive reaction when the danger has passed. This helps us understand how we can develop a neurosis: An excessively intense and prolonged reaction to stress results in chemicals being mobilized for the defense reaction, and not just the immediate fine-tuned bio-electrical neuronal patterns. The disadvantage is that the chemical mechanism does not stop as rapidly as the neuronal mechanism. Thus our emotions do not “calm down” after the provocation.
The VVC is regulated by the brainstem Ambiguous Nucleus.
This higher visceral system, the VVC social interaction system, first emerged with mammals and developed still further in human beings. The VVC allows us to make rapid and subtle changes in our visceral staste as we create social contact, coming closer to the other with parasympathetic visceral opening, and withdrawing from the other with sympathetic visceral closing. This higher level social interaction visceral system has strong connections with the brain’s highest levels: the orbitofrontal lobe and the cingulate gyrus.
A Summary
To summarize how these three visceral levels regulate our behavioural and emotional life:
First Level (DVC): “play dead,” “freeze,” “inner collapse,” “everything lost” when there is sudden bad news.
Second Level (Paraventricular Nucleus of the Hypothalamus): fight or flight, anger or fear, aggressive approach or fearful flight when we are threatened or attacked.
Third Level (VVC): approach and avoidance, rapid and subtle visceral regulation, during social contact.
When we feel generally good, the VVC predominates. When we are provoked and react in an active way (attacking the opposition or fleeing), our sympathetic fight-flight system is activated. When we are exposed to a situation with a sense of overwhelming disaster (trauma), our DVC “inner collapse” system is mobilized.
The Clinical Consequences of the Multiple Level Visceral System
The clinical consequences of today’s research in neurophysiology will take years to develop. For the moment each clinician is formulating his own hypotheses. Therefore the following section is hypothetical, not written to convince, but merely to stimulate other clinicians to reflect upon their own experience and share with others the neurophysiological – clinical correlations that emerge.
The Multiple Level Visceral Model shows that neurosis is not due to a total pathology of the nervous system. Neurosis is due to an adaptive defense strategy – fight, flight or drop down – that is being called forth at the wrong moment, or being excessively stimulated, or that cannot “calm down” after the danger has passed.
If a person recognizes that he is “over-reacting,” calling forth high energy primitive defense strategies when there is simply a problem of interpersonal approach or distancing, this can be reassuring. He is not “mentally sick,” but using excessively powerful defensive maneuvers.
At the same time, the fact that the emotional experience involves a multiplicity of brain levels –- from the conscious cortex to the various unconscious sub-cortical levels (amygdala, hypothalamus, centray gray matter, locus coeruleus and other neuromodulator secretion centers and, finally, brain stem nuclei) – means that the psychological treatment process must involve all levels. Thus the therapeutic session must exert an impact at all these levels.
Since the amygdala and other sub-cortical centers function according to laws of conditioning, rather than according to the rational laws of conscious insight, the person afflicted with neurotic anxiety, depression, worry or anger, can appreciate that his conscious intentions can be positive. The person can therefore distance himself from his irrational behaviour. “My problem is due to unconscious conditioning. This helps me appreciate my positive qualities. And it encourages me to use these positive qualities to overcome what is automatic and negative, whether this takes place in my feelings, thoughts, attitudes or actions.”
It can also help a person distance himself from other people’s negative automatisms. “That person is under high stress. Therefore his aggressive reaction is automatic and not entirely under his control.” On the other hand, if we are unable to create this psychological distance, very necessary at certain moments, we can become “sucked into” a negative spiral with the other person. “It’s contagious. He raised his voice, and I responded brusquely. It was like we were two wheels of a bicycle. Once we began to roll downhill, we couldn’t stop!” The point is that our awareness of sub-cortical mechanisms of emotion and behaviour help us understand that such unhappy vicious circles are driven by automatic primitive defenses that cannot be turned off by a single positive thought.
Given that we have each been conditioned in the past by such automatic sub-cortical mechanisms, we can each find ourselves vulnerable to a repetition of such unhappy reactions in the future. Therefore, a part of psychological development is to understand our specific “hot points,” avoid situations of provocation, and tune down our response when the conditioned primitive defense is activated.
Social Engagement Vs. Isolation
The “highest level” of visceral functioning – the VVC – involves the presence of another person in a positive relationship. This does not mean that every moment of aloneness creates an automatic return to a primitive defense strategy. The law of “internalization” is a law of learning. The positive Self-Other visceral pattern can be “remembered,” both consciously and unconsciously, even when the positive Other is absent. At least for awhile.
But prolonged absence of a positive Other can permit the emergence of the primitive defense patterns. Examples: Animals reared in isolation, infants left to themselves for prolonged periods (Spitz’ research regarding babies without contact in orphanages), older people abandoned and alone after the death of the spouse, etc. A great deal of research has shown the connection between prolonged isolation and depression. The Three Level Visceral Model explains this loss of higher functions when positive contact with others is loss.
But it also suggests a more subtle dynamic that can involve anyone: If certain important emotions repeat themselves in a person’s experience, but are not shared, this “packet” of sub-cortical/cortical isolation – “Noone can understand me,” “I’m too ashamed to admit it,” “People would take advantage of my weakness,” etc. – can create a neurotic vicious spiral, even within a person who is generally social and in good contact with others.
This mechanism of isolation creating inner vicious spirals can be counter-acted with psychotherapy, as well as by other situations of emotional sharing (Self-Help groups, religious confession, deep friendship, even “prayer” when the God figure, the positive Other, is felt in an intense way.) However, to be effective, these approaches of “sharing one’s deep inner life with a positive Other” require something specific: The person must share the hidden emotion. A phrase from Carl Jung: “We are sick because of our secrets.” The hidden emotion must come forth during the period of sharing. Otherwise the neuronal network of the primitive defence remains isolated from the neuronal networks that emerges during the sharing. And the person who shares feels no essential emotional change.
D.O. Hebb offered a general principle of neuronal functioning which helps explain this requirement of “sharing the hidden feeling:” Hebb said, “Neurons that fire together, wire together.” Therefore, the unwanted primitive defence strategy – visceral levels I and II – must become partially activated in order to become reprogrammed and attached to visceral level III, the social engagement level.
Primordial Emotions
The Porges Model also gives a map which can help the clinician understand complex clinical phenomena: The primitive defence strategies suggest three types of emotion that can occur in an excessive and automatic way: Aggression or fear (Level II) or inner collapse (Level I). Each emotion can correspond to something the person wishes to hide, because it is “too much,” “destructive,” “shameful,” “uncivilized,” “unethical,” etc. In addition, the person can have a feeling of suffering which is yet more complex: “It’s all a confusion inside. The feelings are going in every direction.” Thus we see, clinically, that a person can undergo two different emotions at the very same time. The Porges Multiple Level Viscreral Model can explain this: Two different primitive defence systems can be provoked simultaneously. Thus, for example, a knot in the belly, a tension in the chest, a contraction in the throat, a headache, etc., can each represent a mixture of rage and fear (Level II), or of rage and total desperation (Level II and I), or, as frequently happens, of loss regarding the past and fear for the future.(Level I and II) The therapist, explaining how these automatic emotions can arise, can thereby create a therapeutic alliance with the patient: “You’re not crazy to have these feelings. These are natural tendencies. Sometimes they even have survival value. But for the moment these feelings have gotten out of hand. So our work is to recognize them (allow the neurons to be partially rekindled), and then look at them from other points of view (re-contextualizing).”
From Conscious “Low-Grade” Emotions to Intense Unconscious Emotions
A patient may say, “I’m always worried.” Another: “I’m constantly frustrated.” A third: “I always feel unhappy. As if there’s something missing.” These are ordinary feelings that anyone can feel for the moment. But in certain people the feelings are constant and difficult to change.
Therapist and patient can explore the various meanings of these feelings. Situations that provoke the feelings can be examined and perhaps re-evaluated. But if these feelings remain – constant worry, timidity, withdrawal, refusal -- we may need another explanation: Such constant and unhappy low-grade feelings may be due to “deeper and more intense, but hidden emotions.’ The Three Level Visceral Model offers a map of the brainstem that provides such an explanation. Many psychotherapists might already be using such explanations because of intuition. But Porges’ Model gives a certain intuition objective grounding: “The feelings that we are conscious of are the sign of more intense and painful feelings that have not yet emerged into consciousness.” Let’s return to the above examples:
Conscious Feeling Intense Unconscious Emotion Based on a Primitive Defence Strategy
Worry Intense fear
Frustration Intense anger, rage
Unhappy, something missing Total loss, inner collapse
It is possible that the conscious feeling comes from two or more unconscious emotions. “I feel anxious.” In this case the conscious feeling may be the result of a combination of intense fear, intense rage and total loss, all reaching consciousness at the same time.
Therefore, a frequent feeling that is disturbing, but which does not resolve easily simply by being shared, may be a “derivative” of a primary visceral defence that is buried out of consciousness. This map can encourage the clinician to suggest, at times, “Perhaps this worry (or insecurity, or timidity, or uncertainty, or suspicion, or sense of injustice, or protest) might very well be the sign of another feeling, much more intense, but perhaps also more painful. Is it possible that you have had intense experiences in which the emotion was overwhelming and too hard to bear? Even if you don’t have particular memories now, is it possible that such intense episodes have occurred?”
The patient who says, “Yes,” or “Perhaps,” shows that he is ready, at least in his conscious intention, to work on a deeper level. To repeat, this concept is not new for psychotherapists. And very often the deep listening of the therapeutic session allows the patient to spontaneously access the buried experience, thus giving confirmation for therapist’s intuition. What is new is that Porges’ Model gives a neurophysiological support for this hypothesis.
In addition, the model gives “sense” to deeper emotions without calling them “pathological,” “abnormal” or “crazy.” The fact that they come from a phylogenetic ancestral strategy for defence – fight, flight or drop – allows the patient to maintain his self-esteem in front of such intense emotions that are rarely expressed openly in daily life. “Other people are not like this.” Response: “We are all like this, deep down. We all have these intense survival strategies. The problem is that we become overwhelmed by the emotion, and then it becomes repressed. It’s outside of consciousness, but still working away, like a machine that runs out of control. We can suffer from the consequences: constant worry, headaches, a constant knot in the stomach, a constant feeling of inferiority or guilt. If we can get to the bottom of it, we will be less bothered by this intense emotion.”
The neurophysiological map of our sub-cortical system – amygdala, hypothalamus, central gray matter, neuromodulator-producing nuclei, visceral nuclei, etc. – all justify this psychological explanation. Thus the Porges model, as well as other research involving the sub-cortical underpinnings of emotion – LeDoux (1996) on the amygdala, Laborit (1969) and Shore (1994) on the whole limbic system, Gellhorn (1967) on the hypothalamus, Edelman (1989) on the neuromodulator-producing nuclei, etc. – all contribute in giving us a fuller understanding of our emotional depths.
In summary, the Porges Model of Three Levels of Visceral Reaction can help the psychotherapist explain to the patient the “automatic” basis of his emotions and create a therapeutic alliance for relief and improvement.
Edelman, Gerard M., The Remembered Present, New York, BasicBooks, 1989.
Gellhorn, Ernst, Principles of Autonomic-Somatic Integration: Physiological Basis and Psychological and Clinical Implication, Minneapolis, University of Minnesota Free Press, 1967
Laborit, Henri, Inibition of Action, Paris, Masson Pub., 1969.
LeDoux, Joseph, The Emotional Brain, New York, Phoenix, 1996.
Nauta, Walle, “The Central Viscermotor System; a General Survey”, (pp.21-39), from Hockman, Charles H. (Editor), Limbic System Mechanism and Autonomic Functions, Springfield, Ill., Charles C. Thomas Publ., 1972
Porges, Stephen W., “Emotion: An Evolutionary By-Product of the Neural Regulation of the Autonomic Nervous System” NYAS Neurobiology of Affiliation , 10/08/1996
Porges, Stephen W., “Social Engagement and Attachment: A Phylogenetic Perspective”
Roots of Mental Illness in Children, Annals of the New York Academy of Sciences.
Porges, Stephen W., “The Polyvagal Theory: phylogenetic contributions to social behavior”,
Physiology & Behavior 79 (2003) 503– 513
Porges, Stephen W., “The Polyvagal Theory: Phylogenetic Substrates of a Social Nervous System”
International Journal of Psychophysiology, 42 (2001) 123-146
Schore, Allan N., Affect Regulation and the Origin of the Self (The Neurobiology of Emotional Development), Lawrence Erlbaum Associates, Publishers, 1994.